I am looking for a cause for icing on the interior windows of my car, including the sunroof. When it rains heavily I am seeing moisture on the interior windows and on the ceiling. On occasion the doors will freeze and will not shut.

I have brought the car into a the dealership and they couldn't pinpoint a cause.

Any suggestions?

 

Did you spill cake in your car?

Anyway, ICE inside is probably either just the snow melting from your carpets, evaporating and freezing again, or it is a leak from sunroof/door/etc..

 

The interior humidity is too high thats for sure. That moisture thats freezing is coming from somewhere. Make sure your carpets and the seats if they are cloth are dry. Run the HVAC system with the recirculate button on outside air, and use the A/C in on poisition and heat on warm to help remove moisture.

 

I worked in Tennesee one winter and I saw a lot of iced up windows. It ices up because you southerners don't like to open your windows in the winter.
I live in Canada and opening your windows in the winter is a fact of life.
Just open the window a crack and the moisture in your car will exit out the crack.
Ice and moisture condense on the cold windows inside your car. This is just physics or did you miss that class? The moisture is from you and the occupants of your car. There is no technical problem with your car. Ask any northerner and this is what they will tell you.

 

As well set the controls to "outside air" and not "recirculating air". This will help greatly.

 

For the moisture you actually set it to recirculate and turn the A/C on since it is a condenser and removes the moisture.

 

how old is your car? alot of times foggy windows can be from a dirty old cabin filter.